Research On Several Scheduling Problems Based On Maintenance Activities

In the classical scheduling problems,the machine can continue processing until the processing is completed.However,in the actual production process,due to factors such as deterioration effects and machine failures,the production efficiency is reduced,so it is necessary to carry out maintenance activities on the machine to improve its production efficiency.This article studies several types of scheduling problems with maintenance activities.The first chapter introduces the research background and significance of this article,related research progress at home and abroad,and the main ideas and chapter arrangement of this article.The second chapter studies the maintenance scheduling problem with a deterioration effect.Suppose that the machine produces a deterioration effect during the production process and performs a maintenance activity at a certain moment.Considering the problem of minimizing the total absolute differences in completion times and the total absolute differences in waiting times,when the maintenance time is a fixed constant,the problem can be solved in polynomial time,and the time complexity is O(n2 log n),where n is the number of jobs.In addition,this problem can be extended to a general scheduling objective function.The third chapter considers the maintenance scheduling problem with common due-window assignment.Assuming that all the jobs share a due-window,the actual processing time of the job is divided into constant processing time and processing time with deterioration effect.The objective function is the weighted sum of the earliness,tardiness,number of early,number of delayed,starting time and size of due-window.We prove that the above problem remains solvable in polynomial time,and the time complexity is O(n6).Chapter 4 extends the problem to parallel machines,and studies the unrelated parallel machines scheduling problems with deterioration effects and maintenance activities,the objective is to minimize the total completion time and total machine load.The model can be further extended to the identical parallel machines.It is proved that the above problems are solvable in polynomial time,and the time complexity is O(n2m+2),where m is the number of processors.Chapter 5 summarizes the contents of this article.